NAME

SYNOPSIS

DESCRIPTION

The
sleep
utility will suspend execution for
at least the integral number of seconds specified by the
time
operand.

OPTIONS

None.

OPERANDS

The following operands are supported:

time

A non-negative decimal integer specifying
the number of seconds for which to suspend execution.

STDIN

Not used.

INPUT FILES

None.

ENVIRONMENT VARIABLES

The following environment variables affect the execution of
sleep:

LANG

Provide a default value for the internationalisation variables
that are unset or null.
If
LANG
is unset or null, the corresponding value from the
implementation-dependent default locale will be used.
If any of the internationalisation variables contains an invalid setting, the
utility will behave as if none of the variables had been defined.

LC_ALL

If set to a non-empty string value,
override the values of all the other internationalisation variables.

LC_CTYPE

Determine the
locale for the interpretation of sequences of bytes of text data as
characters (for example, single- as opposed to multi-byte characters
in arguments).

LC_MESSAGES

Determine the locale that should be used to affect
the format and contents of diagnostic
messages written to standard error.

NLSPATH

Determine the location of message catalogues
for the processing of
LC_MESSAGES .

ASYNCHRONOUS EVENTS

If the
sleep
utility receives a SIGALRM signal, one of the following
actions will be taken:

Terminate normally with a zero exit status.

Effectively ignore the signal.

Provide the default behaviour for signals described in the
ASYNCHRONOUS EVENTS section of
Utility Description Defaults.
This could include terminating with a non-zero exit status.

The
sleep
utility will take the standard action for all other signals.

STDOUT

Not used.

STDERR

Used only for diagnostic messages.

OUTPUT FILES

None.

EXTENDED DESCRIPTION

None.

EXIT STATUS

The following exit values are returned:

0

The execution was successfully suspended for at least
time
seconds, or a SIGALRM signal was received (see
the ASYNCHRONOUS EVENTS section).

>0

An error occurred.

CONSEQUENCES OF ERRORS

Default.

APPLICATION USAGE

None.

EXAMPLES

The
sleep
utility can be used to execute a command
after a certain amount of time, as in: